植物生态学报 ›› 2022, Vol. 46 ›› Issue (7): 811-822.DOI: 10.17521/cjpe.2021.0280

• 研究论文 • 上一篇    下一篇

氮添加促进丛枝菌根真菌和根系协作维持土壤磷有效性

谢欢1, 张秋芳2, 陈廷廷1, 曾泉鑫1, 周嘉聪1, 吴玥1, 林惠瑛1, 刘苑苑1, 尹云锋1, 陈岳民1,*()   

  1. 1福建师范大学地理科学学院, 湿润亚热带山地生态国家重点实验室培育基地, 福州 350007
    2北京大学城市与环境学院, 北京 100871
  • 收稿日期:2021-08-02 接受日期:2021-12-09 出版日期:2022-07-20 发布日期:2022-01-07
  • 通讯作者: 陈岳民
  • 作者简介:* (ymchen@fjnu.edu.cn)
  • 基金资助:
    福建省自然科学基金(2020J01142)

Interaction of soil arbuscular mycorrhizal fungi and plant roots acts on maintaining soil phosphorus availability under nitrogen addition

XIE Huan1, ZHANG Qiu-Fang2, CHEN Ting-Ting1, ZENG Quan-Xin1, ZHOU Jia-Cong1, WU Yue1, LIN Hui-Ying1, LIU Yuan-Yuan1, YIN Yun-Feng1, CHEN Yue-Min1,*()   

  1. 1State Key Laboratory of Subtropical Mountain Ecology, School of Geographical Science, Fujian Normal University, Fuzhou 350007, China
    2College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
  • Received:2021-08-02 Accepted:2021-12-09 Online:2022-07-20 Published:2022-01-07
  • Contact: CHEN Yue-Min
  • Supported by:
    Natural Science Foundation of Fujian Province(2020J01142)

摘要:

磷是亚热带地区植物生长的主要限制营养元素, 而氮沉降量的增加会降低土壤磷的有效性。该研究以微生物和植物细根为重点探究土壤磷转化, 揭示氮沉降背景下低磷有效性土壤的磷供应及生产力维持。通过在福州长安山模拟氮沉降实验, 设置对照(0 kg·hm-2·a-1)、低氮(40 kg·hm-2·a-1)和高氮(80 kg·hm-2·a-1) 3个处理, 收集杉木(Cunninghamia lanceolata)幼苗的土壤和根系样本, 综合分析土壤磷组分和养分含量、土壤微生物特征和植物根系特征。结果显示, 与对照处理相比, 低氮处理显著增加土壤易分解态有机磷、中等易分解态无机磷和闭蓄态磷含量, 但是显著降低原生矿物态磷和中等易分解态有机磷含量; 而高氮处理对土壤磷组分无显著影响。冗余分析表明, 土壤酸性磷酸酶活性、丛枝菌根真菌的相对丰度、土壤微生物生物量磷含量和根系生物量是解释土壤磷组分变化的重要微生物和植物因子。方差分解分析发现植物根系特征-土壤微生物特征共同解释了土壤磷组分变化的57%, 并且通过相关分析发现丛枝菌根真菌的相对丰度和根系生物量呈显著正相关关系。综上所述, 低水平的氮输入促进土壤丛枝菌根真菌的定殖, 丛枝菌根真菌和杉木根系通过协作促进中等易分解态有机磷和原生矿物态磷向易分解态磷的转换, 维持了杉木幼苗的生长。

关键词: 氮添加, 磷, 微生物特征, 根系特征, 杉木, 幼苗

Abstract:

Aims Phosphorus is one of the major limiting nutrients for plant growth in subtropical areas, whereas increasing nitrogen deposition may be a limiting factor in determining the availability of soil phosphorus. Here, focusing on soil microorganisms and plant fine roots, we explored the transformation of soil phosphorus to unravel the maintenance of soil phosphorus supply and plant productivity with low availability under nitrogen deposition.

Methods At the Fuzhou Changʼan Mountain in Fujian Province, China, control (0 kg·hm-2·a-1), low nitrogen (40 kg·hm-2·a-1), and high nitrogen (80 kg·hm-2·a-1) treatments were set up to simulate nitrogen addition. Soil and root samples of Cunninghamia lanceolata seedlings were then collected to comprehensively analyze soil phosphorus and nutrient contents as well as microbiological-plant root characteristics.

Important findings The results showed that the contents of soil labile organic phosphorus, moderately labile inorganic phosphorus and occluded phosphorus were significantly increased, whereas those of primary mineral phosphorus and moderately labile organic phosphorus decreased under the low nitrogen treatment as compared to the control treatment. However, there were no significant changes under the high nitrogen treatment. Redundancy analysis indicated that soil acid phosphatase activity, relative abundance of mycorrhizal fungi, soil microbial biomass phosphorus content, and root biomass were important soil microbiological-plant root characteristics factors that could explain the changes in soil phosphorus components. Variance partitioning analysis revealed that the soil microbiological-plant root characteristics synergy explained 57% of the alternations in soil phosphorus components, whereas correlation analysis showed a significant positive correlation between the relative abundance of mycorrhizal fungi and root biomass. Overall, these results suggest that mycorrhizal colonization is promoted under a low level of nitrogen input and the synergistic action of mycorrhizal fungi and C. lanceolata fine roots promotes the conversion of moderately labile organic and primary mineral phosphorus to labile phosphorus, thus maintaining the growth of C. lanceolata seedlings.

Key words: nitrogen addition, phosphorus, microbiologic characteristic, root characteristic, Cunninghamia lanceolata, seedling